Il-Ġimgħa, 11 ta’ Diċembru 2009

1. Qualia and (some) of their discontentsQualia are often posited to account for our sensory experience. They are a plausible thing to posit, at the face of it. There should be a qualitative element of perceptual experience that cannot be fully understood in terms of anything like beliefs, disposition to behave or mere neuron firings. These qualitative elements account for the distinctive sensations of cold connected to the water in a mountain stream, of the overwhelming blueness of the deep ocean, of the acute pain associated to cutting oneself in a sharp stone etc. There is something subjective that remains unexplained no matter how you account for the mind in terms of beliefs and conceptual capacities, dispositions to behave or neuron interactions. The thesis is that any attempt to provide an ontology of the mind should make room for those subjective, qualitative states. Qualia should therefore be accepted unless we can find resources somewhere else to fully explain them away.In a robust formulation, the ontology of qualia takes them to have three related but distinctive features:i. They are private. That is, they cannot be felt by anybody else but by the person who entertain them. They are, in an important sense, subjective.ii. They are indifferent to beliefs and arguably to other propositional attitudes. Qualia are first-personal and cannot be overruled by third-personal considerations. I can find out that there was no dagger in front of me and stop believing there is one, but that cannot rid me of the quale of a dagger in front of me. (This feature can eventually be used to explain illusion situations – like the Miller-Lyer illusion – where we cannot stop ourselves from seeing what we know is not the case.) iii. They are non-acquired. People don't acquire their dispositions to have qualia, or at least not through conceptual education; they come the same way as heartbeat, blood circulation or muscle flexibility. One could enhance one´s capacity to feel things, but a certain minimal amount of qualia is inborn – and that seems important for the adaptation of the species. They don´t depend on concept acquisition nor on any other form of socialization or education. On the face of this formulation, we can either favor some kind of qualia-eliminativism according to which there simply isn't anything like qualia in our mental life, impressions to the contrary notwithstanding (including forms of qualia-reductionism that take to be qualia reduced to other items that are not private, incorrigible or non-acquired) or make room for these odd items in one' s ontology of the mind. We shall not be concerned much with the first option here – but we will say something about its motivations shortly. We shall rather engage in the effort of making sense of a robust ontology of qualia. David Chalmers has argued that there ought to be room in our ontology for subjective items, independently of their capacity to explain and predict other behavioral or functional states. An ontology informed by future physics (perhaps together with future biology, psychology or sociology) would have to be complemented with the postulation of subjective items like qualia. They are part of the furniture of the universe because they cannot be explained away as our subjective experience has an undeniable qualitative character that cannot be ignored. (CHALMERS, 1997). Chalmers then engages in considerations to do, for instance, with inverted qualia: two people could correctly identify, say, the same pair of colors but have inverted qualitative experiences associated to each of them. The idea is that qualia are independent of any recognition ability we might have acquired – and still are individuated in terms of our (color) vocabulary. Analogously, Jackson's Mary is understood as having the qualitative counterpart of red missing while she is in the black and white room. As she was not exposed to anything red, she did not display the ready-made expected subjective state corresponding to the image of something red (JACKSON, 1986). This appeal to a ready-made qualitative state corresponding to bits of our sensory vocabulary has been met with some suspicion. Non-acquired states seem incapable to carve the world at its joints – there cannot be any private (sensory) state waiting to be labeled by our sensory vocabulary, or so runs the suspicion. In the 20th century, Wittgenstein and Sellars have championed variations of this suspicion: the former argued that there is no such thing as private states that can be identified and individuated without the help of our conceptual practices while the latter was convinced that psychological states could not display primacy with respect to our (conceptually and theoretically loaded) sensory vocabulary. Sellars put forward what he called psychological nominalism, a doctrine according to which our mental life is made of particulars (SELLARS, 1991, p. 160).The suspicion has driven many people to recoil from the postulation of qualia. Those subjective, private, incorrigible and non-acquired states seemed implausible on the light of the criticisms of the plausibility of conceptually unaided sensory discrimination, of the arguments against private mental contents or the mistrust of ready-made sensory items. We can refer to this suspicion as problems with the given, for short. If one is nevertheless also convinced of Chalmers' motivation to embrace a robust ontology of qualia, one finds oneself swinging between an acceptance of those subjective states on the one hand – together with the discomfort brought about by the problems with the given – and a rejection of those state on the other – while allowing that the subjective quality of our sensory experience would be left unaccounted. If one is sensitive to both Chalmers' motivation and Wittgenstein and Sellars' suspicion, a dilemma presents itself: either there are qualia and something is given or nothing is given but the subjective character of our sensory experience remains unexplained. In what follows, we will sketch of a way out of the dilemma.

2. Abstractions can be less than universalProperties are usually though of as (abstract) universals. Objects are concrete particulars that could be understood solely in terms of their properties (as varieties of bundle theories have claimed and substrata theories have denied). Nominalists, in general, voice problems with properties – they tend to think that there is little of ontologically substantial associated with predicates. A metaphysical alternative to (universal) properties is to consider tropes – abstract particulars. Keith Campbell has argued that trope theory can provide a way out for the dispute between bundle and substrata accounts of the (concrete particular) objects and vindicate the nominalist dislike of properties. Trope theory can understand both objects and properties as made of the same stuff (CAMPBELL, 1990).Tropes could be monadic or n-adic where n>1: the former are sometimes called qualitons and the latter relatons. Abstract particulars are bound together by some co-presence relation (that could be a provided by a relaton) forming objects. Instead of properties, trope theory takes every predication to involve particularity; 'x is a book' doesn't predicate the same property as 'y is a book' – our predicate 'book' does no more than point at some relevant similarity between x and y; it names no property. The green of a leaf of grass is not the same as the green of another leaf – only they can be relevantly similar, similar enough for us to subject both leaved to the same predication. Trope theory, hence, embraces nominalism at the level of predication: there is something particular and substantial to every predication, the universality is nevertheless imposed on them by our names.A trope ontology typically involves tropes (that compose objects) and relations of co-presence. This is however not enough. In order to provide truth-makers to our (universal) predications – something that we need in order to explain why red things affect bulls in ways that blue ones don't – we need something akin to relations of similitude. There is something similar between all the green qualitons. Tropes and their effects are clustered together in ways that we can successfully capture in our tools for predications. Those clusters are not composed by identities – identities are always approximate. Similarity relations are often taken to be primary items in trope ontologies: instead of abstract universals, abstract particulars and relations of similitude between them.Surely, one could postulate tropes alongside with properties. Trope ontologies could also be mixed ontologies as there could be not only abstract universals but also abstract particulars. One could, for example, understand second-order abstractions to be tropes – objects can be predicated with properties while properties could be predicated with tropes. Or one could understand that there are levels of (ontological) similarity, when tropes are too similar, they constitute a property.

3. Qualia as qualitonsMichael Tye has recently argued that there is no such thing as a quale corresponding to each state of the world; for example, a quale corresponding to every shade of blue someone is capable to detect (TYE, 2006). Tye argues that when two observers disagree as to whether a shade is true blue or greenish blue, there might not be a matter of fact as to which quale is the correct one. It is enough for our species sound adaptation that we have a state corresponding to a reasonably-sized class of shades of blue. He's suggesting an independence between our effective and well-adapted sensory state and the qualia that support them. As far as adaptation (or adequacy to detect what is relevant in the surrounding environment) is concerned, the final sensory state is what matters; the (different) qualia could be no more that the (different) stuff on what this state is instantiated.We are now in a position to suggest that the dilemma in section 1 was due to our attachment to a metaphysics of properties. If we take qualia to be tropes – no matter whether there are (universal) properties in the world – we can bring together the advantages of both horns. On one side, we can make justice to Chalmers' motivations to postulate a robust ontology of qualia as we consider our sensory states as private, subjective, incorrigible by our beliefs and non-acquired in conceptual education. Qualia are abstract particulars that are unaffected by our conceptual tools and indifferent to the uses we make of them to recognize final (conceptually loaded) sensory states like 'green', 'painful' or 'book-shaped'. They are subjective and unrelated to the states postulated by our public vocabulary on sensations – items discriminated by this vocabulary are recognized through our final sensory states that are themselves arrays of qualia. Our sensory concepts cluster our qualia together but they themselves correspond to no basic qualia – qualia are no more than the raw material each of us use to acquire sensory concepts. On the other hand, we can reject the given together with Wittgenstein and Sellars as there is no conceptual content already present in our qualitative sensory states. Qualia, that are qualitons and not properties, are particulars – just as would be recommended by a psychological nominalism – bring themselves no universal content, that is, nothing that can, for instance, be subject to Evans' generality constraint. Hence, it makes scarce sense to talk about inverted qualia as such a condition cannot be recognized – there is no such thing as a green qualia or a red qualia, qualia are states we are when we face specific instances of what we predicate (with the help of our acquired sensory concepts) as green or red. What corresponds to one person's final sensory state of seeing something red is an array of qualitons, each of them (possibly) unique. Jackson's Mary, therefore, is arguably endowed with new qualia when she leaves the black and white room. This means that she now has more resources to recognize something as red. She will now have more qualia, but nothing that can be called a red quale.A qualiton account of qualia should also say something about similarity between sensory tropes. We take similarity relations to be acquired in our sensory concept acquisition. This makes room for Sellars' intuition that there cannot be a ready-made notion of, say, green before we acquire the means to make color predications. There is no natural way to cluster our qualia together; our sensory vocabulary can carve the world in its joints but it would be utterly mysterious if relations of similitude among qualia tropes where capable to carve our sensory vocabulary in its joints. We take the acquisition of sensory concepts to be crucially an acquisition of patterns of similitude between qualia tropes. Qualia are resources available to us in order to learn how to use the sensory vocabulary that is inculcated in us when we acquire a public language. My capacity to recognize something as green depends on my available qualia, and can differ completely from the qualia technology anybody else has learned to use – different in terms of raw sensory states and in terms of the relations of similitude established therewith.

4. Sensations and similitudeIf we consider solely the epistemology of sensations – how they justify our beliefs and how they respond to what there is – we might feel no need to appeal to qualia as qualitons. In fact, they can be of scarce help. Nor can qualia help, on this account, to explain how our sensations can be adaptive. In this sense, because qualia are only clustered together in stable ways after sensory concepts acquisition, the present account differs from Tye's. However, we might be interested in the qualitative sensory state behind our recognition of sensations - in the technology of recognition that is acquired with a public language. An account of qualia that takes them to be tropes while keeping features i-iii above provides a model of acquisition as recognition of relevant relations of similarity (and difference) among qualitons. It can provide a model of what goes on privately while a public language is acquired. In section 304 of the PU, Wittgenstein responds to his interlocutor who asks him “But you will surely admit that there is a difference between pain-behaviour accompanied by pain and pain-behaviour without any pain? (…) And yet you again and again reach the conclusion that the sensation itself is a nothing”. The charge is that our basic qualitative sensory states such as the ones present when we have pain are irrelevant and can be dismissed – it is as if they were not present. Wittgenstein seems to want to say that indeed it is as if they were not present – at least if we describe our mental life in terms of the outcomes of a normal and functioning sensory apparatus – but still there is something present. He responds: “Not at all. It is not a something, but it is not a nothing either! The conclusion was only that a nothing would serve just as well as a something about which nothing can be said.” The sensation, it seems, appears as a presence that cannot be used unaided in any predication – like one would expect of an abstract particular, usable in predication only when coupled with relations of similarity. Yet, the relations of similarity are introduced in our mental life with our concept acquisition and when we reach this point, it seems like they can do the job unaided by any sensation. The message doesn't seem to be that there are no qualia, but rather that there could be qualia if their existence doesn't require that they can be used unaided in predications. The view recommended is therefore one where similarity relations crucial for the acquisition of concepts. One could, however, fear that judgments of similarity cannot get off the ground if all they have to start out with are mere abstract particulars. If one has the qualiton Q and is thought that it resembles (in the relevant conceptual sense) qualiton R, but not qualiton P, how could one compare those qualitons without having them somehow present in the mind? In other words, how can my past qualia be retrieved when I need them to learn similarity relations if they are not (from the start) available to be in a conceptual format? The question resembles the one Wittgenstein poses at section 342 at the Investigations: how can a mute and death person recall thoughts she had before she was introduced to any language, written or otherwise? This is indeed a troublesome area, but we believe we can sketch a way out.Consider one's attention to quale Q. We assume attention is somehow different from predication – I can attend to Q without making a predication of the sort 'Q is φ' (note that the abstract particular is the subject of the possible predication). If I can attend to Q, then we can have it present to the mind, at least sometimes, together with P or R. This should be eventually enough to get the process started – a process of gradual refinement of conceptual formats so that what is roughly red eventually gets refined into different shades of red. Notice that this procedure of attention can be thoroughly private and subjective – it can differ completely from one to another person. Still, we believe this privacy is both enough to make sure qualia as qualitons are useful for concept acquisition and does not violate the kernel of the suspicion against private proto-conceptual contents. All that is required is that we can manage to attend to two qualitons at the same time so that we can start to grasp the notions of similarity and relevant difference.Qualia act as enabling conditions for concept acquisition. They act along with several other states and capacities – among them the capacity to attend to particulars in the world. We start out with particular mental states that respond to particular items in the world – the blue of a lake, the green of a leaf, the coldness of a glass of water. These are responses that we postulate to explain our learning abilities. Our final sensory state will require concepts and we should judge their adaptiveness irrespective of the qualia we have used to acquire them. As mental particulars, qualia are private in the same sense as our genes, our bodies or our voice is private. They are not private in the more robust sense that some people claim that thoughts are private. They are not private contents in the sense that they can provide private predications. But they are subjective and satisfy the first feature mentioned in section 1 . They are particulars that are subsumed by (sensory) concepts when we acquired them; they do justice to the intuition that sensations are there to be predicated by our concepts. They are indifferent to our beliefs and hence they satisfy feature ii – but with a qualification. They cannot themselves, however, explain illusions (such as the Miller-Lyer illusion mentioned above) as they cannot be used unaided in predications. Finally, they are non-acquired.A last point about properties and tropes in general. Qualia understood as qualia are such that relations of similarity are acquired when we acquire conceptual capacities. They are acquired. That, however, implies neither that the world has no properties – only tropes - nor that relations of similarity between world tropes are imposed on them by us. It could be that the only abstract particulars in our ontology are qualia. It could also be that world qualitons are such that the world itself somehow provides relevant relations of similarity that we cannot expect to do more than carve these relations of similarity on their joints. So, it could be that greenish blue and deep blue are relevantly similar as a matter of fact – no matter that we, as users of a particular language, cluster them in different color groups; and no matter that instances of them appear to us as mind tropes waiting to be subsumed by our concepts that aim at capturing the relevant similarities in the world. The thesis that qualia are qualitons is no more than a thesis about our mental life while we acquire and manage sensory concepts. It has no general implications for our ontology of properties or other abstractions. But it has implications for our intuitions about sensations and their relations to concepts. We believe that they begin to turn the general process of concept acquisition intelligible.